100 points! give an example of a closed system other than an island, and name two organisms that would be unable to immigrate of emigrate this system.

the fossil record provides evidence of a common ancestor to many species.

the atomic number of magnesium is 12. its nucleus must contain 12 protons and no electrons. the atomic number of an atom is determined by the number of protons.

magnesium is an electrolyte injection commonly used to treat low magnesium levels in your blood. it is also used to prevent or control seizures in women with preeclampsia or eclampsia.